v3.25.2
Fair Value Measures and Disclosures (Details) - USD ($)
$ in Millions
 6 Months Ended
Jun. 30, 2024
Jun. 30, 2025
Dec. 31, 2024
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Equity Method Investment, Other-than-Temporary Impairment $ 12.4    
Fair Value, Recurring | Fair Value, Inputs, Level 1      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Cash and Cash Equivalents, Fair Value Disclosure   $ 70.6 $ 43.5
Investments, Fair Value Disclosure   132.2 113.1
Fair Value, Recurring | Fair Value, Inputs, Level 1 | Equity Securities      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Equity Securities, FV-NI   32.9 42.3
Fair Value, Recurring | Fair Value, Inputs, Level 1 | Debt Securities      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Debt Securities, Available-for-Sale   1.4 2.4
Fair Value, Recurring | Fair Value, Inputs, Level 1 | Wealth Advisors [Member]      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Investment Owned, Cost   27.3 24.9
Fair Value, Recurring | Fair Value, Inputs, Level 1 | SmartX      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Investment Owned, Cost     0.0
Fair Value, Recurring | Fair Value, Inputs, Level 2      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Cash and Cash Equivalents, Fair Value Disclosure   0.0 0.0
Investments, Fair Value Disclosure   0.0 0.0
Fair Value, Recurring | Fair Value, Inputs, Level 2 | Equity Securities      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Equity Securities, FV-NI   0.0 0.0
Fair Value, Recurring | Fair Value, Inputs, Level 2 | Debt Securities      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Debt Securities, Available-for-Sale   0.0 0.0
Fair Value, Recurring | Fair Value, Inputs, Level 2 | Wealth Advisors [Member]      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Investment Owned, Cost   0.0 0.0
Fair Value, Recurring | Fair Value, Inputs, Level 2 | SmartX      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Investment Owned, Cost     0.0
Fair Value, Recurring | Fair Value, Inputs, Level 3      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Cash and Cash Equivalents, Fair Value Disclosure   0.0 0.0
Investments, Fair Value Disclosure   0.0 24.7
Fair Value, Recurring | Fair Value, Inputs, Level 3 | Equity Securities      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Equity Securities, FV-NI   0.0 0.0
Fair Value, Recurring | Fair Value, Inputs, Level 3 | Debt Securities      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Debt Securities, Available-for-Sale   0.0 0.0
Fair Value, Recurring | Fair Value, Inputs, Level 3 | Wealth Advisors [Member]      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Investment Owned, Cost   0.0 0.0
Fair Value, Recurring | Fair Value, Inputs, Level 3 | SmartX      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Investment Owned, Cost     24.7
Estimate of Fair Value Measurement | Fair Value, Recurring      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Cash and Cash Equivalents, Fair Value Disclosure   70.6 43.5
Investments, Fair Value Disclosure   132.2 137.8
Estimate of Fair Value Measurement | Fair Value, Recurring | Equity Securities      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Equity Securities, FV-NI   32.9 42.3
Estimate of Fair Value Measurement | Fair Value, Recurring | Debt Securities      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Debt Securities, Available-for-Sale   1.4 2.4
Estimate of Fair Value Measurement | Fair Value, Recurring | Wealth Advisors [Member]      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Investment Owned, Cost   $ 27.3 24.9
Estimate of Fair Value Measurement | Fair Value, Recurring | SmartX      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Investment Owned, Cost     $ 24.7